public class Demo2 {
    public static void main(String[] args) {
        MyStack s = new MyStack();
        s.push(12);
        s.push(23);
        s.push(34);
        s.push(45);

        int val = s.pop();
        System.out.println(val);
        val = s.pop();
        System.out.println(val);

        int val2 = s.peek();
        System.out.println(val2);

         val2 = s.peek();
        System.out.println(val2);

        boolean empty = s.isEmmpty();
        System.out.println(empty);
    }
}
